IP subnet calculator
Type an address with its prefix or mask to see the network, its usable range and masks. Split it into smaller subnets, or look up any prefix in the reference tables.
Network181.2.192.0/20
Usable hosts4,094
Subnet mask255.255.240.0
Addresses4,096
- Network address
181.2.192.0- Broadcast address
181.2.207.255- First usable
181.2.192.1- Last usable
181.2.207.254- Usable hosts
- 4,094 (4,096 less the network and broadcast addresses)
- Subnet mask
255.255.240.0- Wildcard mask
0.0.15.255(Cisco ACLs, OSPF)- Prefix length
- /20
- Type
- Public public
- Old class
- B (default /16)
- As numbers
- Hex
B502C000· Integer3036856320to3036860415 - Reverse DNS zones
192.2.181.in-addr.arpa193.2.181.in-addr.arpa194.2.181.in-addr.arpa195.2.181.in-addr.arpa196.2.181.in-addr.arpa197.2.181.in-addr.arpa198.2.181.in-addr.arpa199.2.181.in-addr.arpa200.2.181.in-addr.arpa201.2.181.in-addr.arpa202.2.181.in-addr.arpa203.2.181.in-addr.arpa204.2.181.in-addr.arpa205.2.181.in-addr.arpa206.2.181.in-addr.arpa207.2.181.in-addr.arpa
/20 is not on a 8-bit boundary, so it takes 16 /24 zones.
Binary
| Binary (network bits bold, host bits grey) | Dotted | |
|---|---|---|
| Address | 10110101.00000010.11000000.00000000 | 181.2.192.0 |
| Subnet mask | 11111111.11111111.11110000.00000000 | 255.255.240.0 |
| Network | 10110101.00000010.11000000.00000000 | 181.2.192.0 |
| Broadcast | 10110101.00000010.11001111.11111111 | 181.2.207.255 |
Split into smaller subnets
/21 (2)/22 (4)/23 (8)/24 (16)/25 (32)/26 (64)/27 (128)/28 (256)/29 (512)/30 (1,024)/31 (2,048)/32 (4,096)
181.2.192.0/20 makes 4,096 subnets of /32; the first 256 are listed.
| # | Subnet | Usable hosts range | Broadcast | Hosts |
|---|---|---|---|---|
| 1 | 181.2.192.0/32 | 181.2.192.0 to 181.2.192.0 | — | 1 |
| 2 | 181.2.192.1/32 | 181.2.192.1 to 181.2.192.1 | — | 1 |
| 3 | 181.2.192.2/32 | 181.2.192.2 to 181.2.192.2 | — | 1 |
| 4 | 181.2.192.3/32 | 181.2.192.3 to 181.2.192.3 | — | 1 |
| 5 | 181.2.192.4/32 | 181.2.192.4 to 181.2.192.4 | — | 1 |
| 6 | 181.2.192.5/32 | 181.2.192.5 to 181.2.192.5 | — | 1 |
| 7 | 181.2.192.6/32 | 181.2.192.6 to 181.2.192.6 | — | 1 |
| 8 | 181.2.192.7/32 | 181.2.192.7 to 181.2.192.7 | — | 1 |
| 9 | 181.2.192.8/32 | 181.2.192.8 to 181.2.192.8 | — | 1 |
| 10 | 181.2.192.9/32 | 181.2.192.9 to 181.2.192.9 | — | 1 |
| 11 | 181.2.192.10/32 | 181.2.192.10 to 181.2.192.10 | — | 1 |
| 12 | 181.2.192.11/32 | 181.2.192.11 to 181.2.192.11 | — | 1 |
| 13 | 181.2.192.12/32 | 181.2.192.12 to 181.2.192.12 | — | 1 |
| 14 | 181.2.192.13/32 | 181.2.192.13 to 181.2.192.13 | — | 1 |
| 15 | 181.2.192.14/32 | 181.2.192.14 to 181.2.192.14 | — | 1 |
| 16 | 181.2.192.15/32 | 181.2.192.15 to 181.2.192.15 | — | 1 |
| 17 | 181.2.192.16/32 | 181.2.192.16 to 181.2.192.16 | — | 1 |
| 18 | 181.2.192.17/32 | 181.2.192.17 to 181.2.192.17 | — | 1 |
| 19 | 181.2.192.18/32 | 181.2.192.18 to 181.2.192.18 | — | 1 |
| 20 | 181.2.192.19/32 | 181.2.192.19 to 181.2.192.19 | — | 1 |
| 21 | 181.2.192.20/32 | 181.2.192.20 to 181.2.192.20 | — | 1 |
| 22 | 181.2.192.21/32 | 181.2.192.21 to 181.2.192.21 | — | 1 |
| 23 | 181.2.192.22/32 | 181.2.192.22 to 181.2.192.22 | — | 1 |
| 24 | 181.2.192.23/32 | 181.2.192.23 to 181.2.192.23 | — | 1 |
| 25 | 181.2.192.24/32 | 181.2.192.24 to 181.2.192.24 | — | 1 |
| 26 | 181.2.192.25/32 | 181.2.192.25 to 181.2.192.25 | — | 1 |
| 27 | 181.2.192.26/32 | 181.2.192.26 to 181.2.192.26 | — | 1 |
| 28 | 181.2.192.27/32 | 181.2.192.27 to 181.2.192.27 | — | 1 |
| 29 | 181.2.192.28/32 | 181.2.192.28 to 181.2.192.28 | — | 1 |
| 30 | 181.2.192.29/32 | 181.2.192.29 to 181.2.192.29 | — | 1 |
| 31 | 181.2.192.30/32 | 181.2.192.30 to 181.2.192.30 | — | 1 |
| 32 | 181.2.192.31/32 | 181.2.192.31 to 181.2.192.31 | — | 1 |
| 33 | 181.2.192.32/32 | 181.2.192.32 to 181.2.192.32 | — | 1 |
| 34 | 181.2.192.33/32 | 181.2.192.33 to 181.2.192.33 | — | 1 |
| 35 | 181.2.192.34/32 | 181.2.192.34 to 181.2.192.34 | — | 1 |
| 36 | 181.2.192.35/32 | 181.2.192.35 to 181.2.192.35 | — | 1 |
| 37 | 181.2.192.36/32 | 181.2.192.36 to 181.2.192.36 | — | 1 |
| 38 | 181.2.192.37/32 | 181.2.192.37 to 181.2.192.37 | — | 1 |
| 39 | 181.2.192.38/32 | 181.2.192.38 to 181.2.192.38 | — | 1 |
| 40 | 181.2.192.39/32 | 181.2.192.39 to 181.2.192.39 | — | 1 |
| 41 | 181.2.192.40/32 | 181.2.192.40 to 181.2.192.40 | — | 1 |
| 42 | 181.2.192.41/32 | 181.2.192.41 to 181.2.192.41 | — | 1 |
| 43 | 181.2.192.42/32 | 181.2.192.42 to 181.2.192.42 | — | 1 |
| 44 | 181.2.192.43/32 | 181.2.192.43 to 181.2.192.43 | — | 1 |
| 45 | 181.2.192.44/32 | 181.2.192.44 to 181.2.192.44 | — | 1 |
| 46 | 181.2.192.45/32 | 181.2.192.45 to 181.2.192.45 | — | 1 |
| 47 | 181.2.192.46/32 | 181.2.192.46 to 181.2.192.46 | — | 1 |
| 48 | 181.2.192.47/32 | 181.2.192.47 to 181.2.192.47 | — | 1 |
| 49 | 181.2.192.48/32 | 181.2.192.48 to 181.2.192.48 | — | 1 |
| 50 | 181.2.192.49/32 | 181.2.192.49 to 181.2.192.49 | — | 1 |
| 51 | 181.2.192.50/32 | 181.2.192.50 to 181.2.192.50 | — | 1 |
| 52 | 181.2.192.51/32 | 181.2.192.51 to 181.2.192.51 | — | 1 |
| 53 | 181.2.192.52/32 | 181.2.192.52 to 181.2.192.52 | — | 1 |
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| 55 | 181.2.192.54/32 | 181.2.192.54 to 181.2.192.54 | — | 1 |
| 56 | 181.2.192.55/32 | 181.2.192.55 to 181.2.192.55 | — | 1 |
| 57 | 181.2.192.56/32 | 181.2.192.56 to 181.2.192.56 | — | 1 |
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| 60 | 181.2.192.59/32 | 181.2.192.59 to 181.2.192.59 | — | 1 |
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| 74 | 181.2.192.73/32 | 181.2.192.73 to 181.2.192.73 | — | 1 |
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| 77 | 181.2.192.76/32 | 181.2.192.76 to 181.2.192.76 | — | 1 |
| 78 | 181.2.192.77/32 | 181.2.192.77 to 181.2.192.77 | — | 1 |
| 79 | 181.2.192.78/32 | 181.2.192.78 to 181.2.192.78 | — | 1 |
| 80 | 181.2.192.79/32 | 181.2.192.79 to 181.2.192.79 | — | 1 |
| 81 | 181.2.192.80/32 | 181.2.192.80 to 181.2.192.80 | — | 1 |
| 82 | 181.2.192.81/32 | 181.2.192.81 to 181.2.192.81 | — | 1 |
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| 84 | 181.2.192.83/32 | 181.2.192.83 to 181.2.192.83 | — | 1 |
| 85 | 181.2.192.84/32 | 181.2.192.84 to 181.2.192.84 | — | 1 |
| 86 | 181.2.192.85/32 | 181.2.192.85 to 181.2.192.85 | — | 1 |
| 87 | 181.2.192.86/32 | 181.2.192.86 to 181.2.192.86 | — | 1 |
| 88 | 181.2.192.87/32 | 181.2.192.87 to 181.2.192.87 | — | 1 |
| 89 | 181.2.192.88/32 | 181.2.192.88 to 181.2.192.88 | — | 1 |
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| 98 | 181.2.192.97/32 | 181.2.192.97 to 181.2.192.97 | — | 1 |
| 99 | 181.2.192.98/32 | 181.2.192.98 to 181.2.192.98 | — | 1 |
| 100 | 181.2.192.99/32 | 181.2.192.99 to 181.2.192.99 | — | 1 |
| 101 | 181.2.192.100/32 | 181.2.192.100 to 181.2.192.100 | — | 1 |
| 102 | 181.2.192.101/32 | 181.2.192.101 to 181.2.192.101 | — | 1 |
| 103 | 181.2.192.102/32 | 181.2.192.102 to 181.2.192.102 | — | 1 |
| 104 | 181.2.192.103/32 | 181.2.192.103 to 181.2.192.103 | — | 1 |
| 105 | 181.2.192.104/32 | 181.2.192.104 to 181.2.192.104 | — | 1 |
| 106 | 181.2.192.105/32 | 181.2.192.105 to 181.2.192.105 | — | 1 |
| 107 | 181.2.192.106/32 | 181.2.192.106 to 181.2.192.106 | — | 1 |
| 108 | 181.2.192.107/32 | 181.2.192.107 to 181.2.192.107 | — | 1 |
| 109 | 181.2.192.108/32 | 181.2.192.108 to 181.2.192.108 | — | 1 |
| 110 | 181.2.192.109/32 | 181.2.192.109 to 181.2.192.109 | — | 1 |
| 111 | 181.2.192.110/32 | 181.2.192.110 to 181.2.192.110 | — | 1 |
| 112 | 181.2.192.111/32 | 181.2.192.111 to 181.2.192.111 | — | 1 |
| 113 | 181.2.192.112/32 | 181.2.192.112 to 181.2.192.112 | — | 1 |
| 114 | 181.2.192.113/32 | 181.2.192.113 to 181.2.192.113 | — | 1 |
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| 120 | 181.2.192.119/32 | 181.2.192.119 to 181.2.192.119 | — | 1 |
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| 138 | 181.2.192.137/32 | 181.2.192.137 to 181.2.192.137 | — | 1 |
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| 142 | 181.2.192.141/32 | 181.2.192.141 to 181.2.192.141 | — | 1 |
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| 147 | 181.2.192.146/32 | 181.2.192.146 to 181.2.192.146 | — | 1 |
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| 212 | 181.2.192.211/32 | 181.2.192.211 to 181.2.192.211 | — | 1 |
| 213 | 181.2.192.212/32 | 181.2.192.212 to 181.2.192.212 | — | 1 |
| 214 | 181.2.192.213/32 | 181.2.192.213 to 181.2.192.213 | — | 1 |
| 215 | 181.2.192.214/32 | 181.2.192.214 to 181.2.192.214 | — | 1 |
| 216 | 181.2.192.215/32 | 181.2.192.215 to 181.2.192.215 | — | 1 |
| 217 | 181.2.192.216/32 | 181.2.192.216 to 181.2.192.216 | — | 1 |
| 218 | 181.2.192.217/32 | 181.2.192.217 to 181.2.192.217 | — | 1 |
| 219 | 181.2.192.218/32 | 181.2.192.218 to 181.2.192.218 | — | 1 |
| 220 | 181.2.192.219/32 | 181.2.192.219 to 181.2.192.219 | — | 1 |
| 221 | 181.2.192.220/32 | 181.2.192.220 to 181.2.192.220 | — | 1 |
| 222 | 181.2.192.221/32 | 181.2.192.221 to 181.2.192.221 | — | 1 |
| 223 | 181.2.192.222/32 | 181.2.192.222 to 181.2.192.222 | — | 1 |
| 224 | 181.2.192.223/32 | 181.2.192.223 to 181.2.192.223 | — | 1 |
| 225 | 181.2.192.224/32 | 181.2.192.224 to 181.2.192.224 | — | 1 |
| 226 | 181.2.192.225/32 | 181.2.192.225 to 181.2.192.225 | — | 1 |
| 227 | 181.2.192.226/32 | 181.2.192.226 to 181.2.192.226 | — | 1 |
| 228 | 181.2.192.227/32 | 181.2.192.227 to 181.2.192.227 | — | 1 |
| 229 | 181.2.192.228/32 | 181.2.192.228 to 181.2.192.228 | — | 1 |
| 230 | 181.2.192.229/32 | 181.2.192.229 to 181.2.192.229 | — | 1 |
| 231 | 181.2.192.230/32 | 181.2.192.230 to 181.2.192.230 | — | 1 |
| 232 | 181.2.192.231/32 | 181.2.192.231 to 181.2.192.231 | — | 1 |
| 233 | 181.2.192.232/32 | 181.2.192.232 to 181.2.192.232 | — | 1 |
| 234 | 181.2.192.233/32 | 181.2.192.233 to 181.2.192.233 | — | 1 |
| 235 | 181.2.192.234/32 | 181.2.192.234 to 181.2.192.234 | — | 1 |
| 236 | 181.2.192.235/32 | 181.2.192.235 to 181.2.192.235 | — | 1 |
| 237 | 181.2.192.236/32 | 181.2.192.236 to 181.2.192.236 | — | 1 |
| 238 | 181.2.192.237/32 | 181.2.192.237 to 181.2.192.237 | — | 1 |
| 239 | 181.2.192.238/32 | 181.2.192.238 to 181.2.192.238 | — | 1 |
| 240 | 181.2.192.239/32 | 181.2.192.239 to 181.2.192.239 | — | 1 |
| 241 | 181.2.192.240/32 | 181.2.192.240 to 181.2.192.240 | — | 1 |
| 242 | 181.2.192.241/32 | 181.2.192.241 to 181.2.192.241 | — | 1 |
| 243 | 181.2.192.242/32 | 181.2.192.242 to 181.2.192.242 | — | 1 |
| 244 | 181.2.192.243/32 | 181.2.192.243 to 181.2.192.243 | — | 1 |
| 245 | 181.2.192.244/32 | 181.2.192.244 to 181.2.192.244 | — | 1 |
| 246 | 181.2.192.245/32 | 181.2.192.245 to 181.2.192.245 | — | 1 |
| 247 | 181.2.192.246/32 | 181.2.192.246 to 181.2.192.246 | — | 1 |
| 248 | 181.2.192.247/32 | 181.2.192.247 to 181.2.192.247 | — | 1 |
| 249 | 181.2.192.248/32 | 181.2.192.248 to 181.2.192.248 | — | 1 |
| 250 | 181.2.192.249/32 | 181.2.192.249 to 181.2.192.249 | — | 1 |
| 251 | 181.2.192.250/32 | 181.2.192.250 to 181.2.192.250 | — | 1 |
| 252 | 181.2.192.251/32 | 181.2.192.251 to 181.2.192.251 | — | 1 |
| 253 | 181.2.192.252/32 | 181.2.192.252 to 181.2.192.252 | — | 1 |
| 254 | 181.2.192.253/32 | 181.2.192.253 to 181.2.192.253 | — | 1 |
| 255 | 181.2.192.254/32 | 181.2.192.254 to 181.2.192.254 | — | 1 |
| 256 | 181.2.192.255/32 | 181.2.192.255 to 181.2.192.255 | — | 1 |
IPv4 CIDR reference (/0 to /32)
| Prefix | Subnet mask | Wildcard | Addresses | Usable hosts | Size | Typical use |
|---|---|---|---|---|---|---|
| /0 | 0.0.0.0 | 255.255.255.255 | 4,294,967,296 | 4,294,967,294 | 16,777,216 × /24 | |
| /1 | 128.0.0.0 | 127.255.255.255 | 2,147,483,648 | 2,147,483,646 | 8,388,608 × /24 | |
| /2 | 192.0.0.0 | 63.255.255.255 | 1,073,741,824 | 1,073,741,822 | 4,194,304 × /24 | |
| /3 | 224.0.0.0 | 31.255.255.255 | 536,870,912 | 536,870,910 | 2,097,152 × /24 | |
| /4 | 240.0.0.0 | 15.255.255.255 | 268,435,456 | 268,435,454 | 1,048,576 × /24 | |
| /5 | 248.0.0.0 | 7.255.255.255 | 134,217,728 | 134,217,726 | 524,288 × /24 | |
| /6 | 252.0.0.0 | 3.255.255.255 | 67,108,864 | 67,108,862 | 262,144 × /24 | |
| /7 | 254.0.0.0 | 1.255.255.255 | 33,554,432 | 33,554,430 | 131,072 × /24 | |
| /8 | 255.0.0.0 | 0.255.255.255 | 16,777,216 | 16,777,214 | 65,536 × /24 | Old class A; 10.0.0.0/8 |
| /9 | 255.128.0.0 | 0.127.255.255 | 8,388,608 | 8,388,606 | 32,768 × /24 | |
| /10 | 255.192.0.0 | 0.63.255.255 | 4,194,304 | 4,194,302 | 16,384 × /24 | |
| /11 | 255.224.0.0 | 0.31.255.255 | 2,097,152 | 2,097,150 | 8,192 × /24 | |
| /12 | 255.240.0.0 | 0.15.255.255 | 1,048,576 | 1,048,574 | 4,096 × /24 | 172.16.0.0/12 |
| /13 | 255.248.0.0 | 0.7.255.255 | 524,288 | 524,286 | 2,048 × /24 | |
| /14 | 255.252.0.0 | 0.3.255.255 | 262,144 | 262,142 | 1,024 × /24 | |
| /15 | 255.254.0.0 | 0.1.255.255 | 131,072 | 131,070 | 512 × /24 | |
| /16 | 255.255.0.0 | 0.0.255.255 | 65,536 | 65,534 | 256 × /24 | Old class B; 192.168.0.0/16 |
| /17 | 255.255.128.0 | 0.0.127.255 | 32,768 | 32,766 | 128 × /24 | |
| /18 | 255.255.192.0 | 0.0.63.255 | 16,384 | 16,382 | 64 × /24 | |
| /19 | 255.255.224.0 | 0.0.31.255 | 8,192 | 8,190 | 32 × /24 | |
| /20 | 255.255.240.0 | 0.0.15.255 | 4,096 | 4,094 | 16 × /24 | |
| /21 | 255.255.248.0 | 0.0.7.255 | 2,048 | 2,046 | 8 × /24 | |
| /22 | 255.255.252.0 | 0.0.3.255 | 1,024 | 1,022 | 4 × /24 | Large office or guest Wi-Fi (1,022 hosts) |
| /23 | 255.255.254.0 | 0.0.1.255 | 512 | 510 | 2 × /24 | Larger office LAN (510 hosts) |
| /24 | 255.255.255.0 | 0.0.0.255 | 256 | 254 | 1 × /24 | Typical office LAN (old class C) |
| /25 | 255.255.255.128 | 0.0.0.127 | 128 | 126 | 1/2 of a /24 | Smaller LAN or VLAN |
| /26 | 255.255.255.192 | 0.0.0.63 | 64 | 62 | 1/4 of a /24 | Smaller LAN or VLAN |
| /27 | 255.255.255.224 | 0.0.0.31 | 32 | 30 | 1/8 of a /24 | Small VLAN, phones, cameras |
| /28 | 255.255.255.240 | 0.0.0.15 | 16 | 14 | 1/16 of a /24 | Small VLAN, phones, cameras |
| /29 | 255.255.255.248 | 0.0.0.7 | 8 | 6 | 1/32 of a /24 | Small fixed public block (5 usable) |
| /30 | 255.255.255.252 | 0.0.0.3 | 4 | 2 | 1/64 of a /24 | Point-to-point (old style) |
| /31 | 255.255.255.254 | 0.0.0.1 | 2 | 2 | 1/128 of a /24 | Point-to-point link (RFC 3021) |
| /32 | 255.255.255.255 | 0.0.0.0 | 1 | 1 | 1/256 of a /24 | One host |
IPv6 prefix reference
| Prefix | Addresses | /64 LANs | /48 sites | Nibble | Typical use |
|---|---|---|---|---|---|
| /3 | 42,535,295,865,117,307,932,921,825,928,971,026,432 (2^125) | 2,305,843,009,213,693,952 | 35,184,372,088,832 | No | All global unicast (2000::/3) |
| /16 | 5,192,296,858,534,827,628,530,496,329,220,096 (2^112) | 281,474,976,710,656 | 4,294,967,296 | Yes | |
| /20 | 324,518,553,658,426,726,783,156,020,576,256 (2^108) | 17,592,186,044,416 | 268,435,456 | Yes | Large provider allocation (RIPE minimum for some) |
| /29 | 633,825,300,114,114,700,748,351,602,688 (2^99) | 34,359,738,368 | 524,288 | No | RIPE allocation to a provider (often) |
| /32 | 79,228,162,514,264,337,593,543,950,336 (2^96) | 4,294,967,296 | 65,536 | Yes | Provider allocation (RIPE default) |
| /36 | 4,951,760,157,141,521,099,596,496,896 (2^92) | 268,435,456 | 4,096 | Yes | |
| /40 | 309,485,009,821,345,068,724,781,056 (2^88) | 16,777,216 | 256 | Yes | |
| /44 | 19,342,813,113,834,066,795,298,816 (2^84) | 1,048,576 | 16 | Yes | |
| /48 | 1,208,925,819,614,629,174,706,176 (2^80) | 65,536 | 1 | Yes | One site or organisation (RIPE PI / assignment) |
| /52 | 75,557,863,725,914,323,419,136 (2^76) | 4,096 | Yes | ||
| /56 | 4,722,366,482,869,645,213,696 (2^72) | 256 | Yes | Small site or home (common provider assignment) | |
| /60 | 295,147,905,179,352,825,856 (2^68) | 16 | Yes | Some home broadband (16 LANs) | |
| /64 | 18,446,744,073,709,551,616 (2^64) | 1 | Yes | One LAN or VLAN (needed for SLAAC) | |
| /72 | 72,057,594,037,927,936 (2^56) | 1/256 of a /64 | Yes | ||
| /80 | 281,474,976,710,656 (2^48) | 1/65,536 of a /64 | Yes | ||
| /96 | 4,294,967,296 | 1/4,294,967,296 of a /64 | Yes | Embeds an IPv4 address (NAT64) | |
| /112 | 65,536 | 1/281,474,976,710,656 of a /64 | Yes | ||
| /120 | 256 | 1/72,057,594,037,927,936 of a /64 | Yes | ||
| /124 | 16 | 1/1,152,921,504,606,846,976 of a /64 | Yes | ||
| /126 | 4 | 1/4,611,686,018,427,387,904 of a /64 | No | ||
| /127 | 2 | 1/9,223,372,036,854,775,808 of a /64 | No | Point-to-point link (RFC 6164) | |
| /128 | 1 | 1/18,446,744,073,709,551,616 of a /64 | Yes | One host or loopback |
Private and special ranges
IPv4
| Range | Name | What it is |
|---|---|---|
255.255.255.255/32 | Limited broadcast | Every host on the local network |
0.0.0.0/8 | This network | Not routed; 0.0.0.0 means "any address" in settings |
10.0.0.0/8 | Private (RFC 1918) | Office and home networks; not routed on the internet |
100.64.0.0/10 | Shared address space (CGNAT) | Used by providers behind carrier-grade NAT (RFC 6598) |
127.0.0.0/8 | Loopback | This computer |
169.254.0.0/16 | Link-local (APIPA) | Self-assigned when no DHCP server answers |
172.16.0.0/12 | Private (RFC 1918) | Office and home networks; not routed on the internet |
192.0.0.0/24 | IETF protocol assignments | Special uses such as DS-Lite |
192.0.2.0/24 | Documentation (TEST-NET-1) | For examples; never used on a network |
192.88.99.0/24 | 6to4 relay (deprecated) | Formerly anycast for 6to4 |
192.168.0.0/16 | Private (RFC 1918) | Office and home networks; not routed on the internet |
198.18.0.0/15 | Benchmarking | Network equipment testing (RFC 2544) |
198.51.100.0/24 | Documentation (TEST-NET-2) | For examples; never used on a network |
203.0.113.0/24 | Documentation (TEST-NET-3) | For examples; never used on a network |
224.0.0.0/4 | Multicast | One-to-many traffic, such as IPTV and routing protocols |
240.0.0.0/4 | Reserved | Future use; not usable on most systems |
IPv6
| Range | Name | What it is |
|---|---|---|
::/128 | Unspecified | No address; :: means "any address" in settings |
::1/128 | Loopback | This computer |
::ffff:0:0/96 | IPv4-mapped | An IPv4 address written as IPv6 |
64:ff9b::/96 | NAT64 | IPv4 addresses reached through a NAT64 gateway |
100::/64 | Discard only | Traffic sent here is dropped (RFC 6666) |
2001:db8::/32 | Documentation | For examples; never used on a network |
2001::/32 | Teredo | IPv6 tunnelled over IPv4 UDP |
2002::/16 | 6to4 | IPv6 tunnelled over IPv4 (largely retired) |
3fff::/20 | Documentation | For examples (RFC 9637) |
fc00::/7 | Unique local (ULA) | Private IPv6, like RFC 1918; usually fd00::/8 |
fe80::/10 | Link-local | Every IPv6 interface has one; not routed |
ff00::/8 | Multicast | One-to-many traffic; replaces broadcast |
2000::/3 | Global unicast | Public internet addresses |